The Best Waterproof Membrane for Exterior Tile

Waterproof membranes are important for tile installations because they protect the substrate and other materials behind the tile installation from water damage. Since cement naturally breathes moisture in and out -- not to mention that exterior conditions expose the tile to rain and weather -- water protection is critical. A couple of membrane systems work well with exterior settings.

Liquid

Liquid waterproofing is the easiest to use and the most common type of membrane available in home improvement stores. Liquid membranes are composed of latex and other components in liquid form inside a container. Once the membrane has been applied to the subsurface, it dries into a thin, waterproof layer of hardened waterproofing, and tile can be laid on top.

Sheet

On the expensive end of things for waterproofing systems are sheet membranes, which are rolled-up sheets of waterproof fabric with a tar-based adhesive on the back. These membranes are meant to be installed in strips across your installation surface, with each new strip overlapping the next by an inch or two until your area is covered.

Painting

Liquid waterproofing is considered the best by some professionals because of its ease of application and affordability in comparison to other waterproofing protocols. You can paint it on with a paintbrush or roller, just like applying a layer of paint. Once everything hardens, the waterproofing membrane also provides anti-fracture protection.

Prep for Sheets

While sheet membranes are considered superior because of their flexibility and protection, the prep adds to the overall cost. The area must be completely clean and you need to paint on a latex primer before you layer the surface with membrane sheets. The installation is more difficult because air bubbles cannot get trapped beneath the membrane.